The fire, which occurred in Waikaia overnight on February 21, 2024, damaged an Elswick St house and two vehicles on the property, about 50km north of Gore.
"Thankfully there were no injuries," Detective Sergeant Brian McKinney said in a statement.
Police earlier called for sightings of vehicles in the area at the time, and said the fire could be linked to previous thefts from the property.
Det Sgt McKinney said police were determined to hold the person responsible accountable, "and while an offender has not been located at this stage, we’re making progress to an arrest".
"There are positive leads in our investigation that we are looking into. However we continue to appeal to the public for any information they have on this incident."
Police appreciated the incident occurred "some time ago".
"However any information provided by the public could be pivotal to the investigation.
"We know there are people out there who may know something about this house fire, and we would like them to get in touch."
Police — reference number 240222/8704, or Crime Stoppers 0800 555 111. — APL
